{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T07:25:28Z","timestamp":1777447528835,"version":"3.51.4"},"reference-count":57,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,3,24]],"date-time":"2017-03-24T00:00:00Z","timestamp":1490313600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Today, significant attention has been brought to the development of sensitive, specific, cheap, and reliable sensors for real-time monitoring. Molecular imprinting technology is a versatile and promising technology for practical applications in many areas, particularly chemical sensors. Here, we present a chemical sensor for detecting formaldehyde, a toxic common indoor pollutant gas. Polypyrrole-based molecularly-imprinted polymer (PPy-based MIP) is employed as the sensing recognition layer and synthesized on a titanium dioxide nanotube array (TiO2-NTA) for increasing its surface-to-volume ratio, thereby improving the sensor performance. Our sensor selectively detects formaldehyde in the parts per million (ppm) range at room temperature. It also shows a long-term stability and small fluctuation to humidity variations. These are attributed to the thin fishnet-like structure of the PPy-based MIP on the highly-ordered and vertically-aligned TiO2-NTA.<\/jats:p>","DOI":"10.3390\/s17040675","type":"journal-article","created":{"date-parts":[[2017,3,24]],"date-time":"2017-03-24T11:38:27Z","timestamp":1490355507000},"page":"675","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":71,"title":["A Formaldehyde Sensor Based on Molecularly-Imprinted Polymer on a TiO2 Nanotube Array"],"prefix":"10.3390","volume":"17","author":[{"given":"Xiaohui","family":"Tang","sequence":"first","affiliation":[{"name":"ICTEAM, Universit\u00e9 catholique de Louvain (UCL), Place du Levant, 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Pierre","family":"Raskin","sequence":"additional","affiliation":[{"name":"ICTEAM, Universit\u00e9 catholique de Louvain (UCL), Place du Levant, 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Driss","family":"Lahem","sequence":"additional","affiliation":[{"name":"Department of Materials Science, Materia Nova ASBL, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arnaud","family":"Krumpmann","sequence":"additional","affiliation":[{"name":"Materials Science Department, University of Mons, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andr\u00e9","family":"Decroly","sequence":"additional","affiliation":[{"name":"Materials Science Department, University of Mons, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marc","family":"Debliquy","sequence":"additional","affiliation":[{"name":"Materials Science Department, University of Mons, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1929","DOI":"10.1016\/S1352-2310(02)00176-0","article-title":"Inter-comparison of air pollutant concentrations in different indoor environments in Hong Kong","volume":"36","author":"Lee","year":"2002","journal-title":"Atmos. 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